Winter Strip Down and Rebuild (Done and Dusted)

[Mikie711]

After a bit of investigation this damage is indicative of oil film break down i.e. not enough oil and probably happened before the oil cooler had filled and oil pressure came up. This shouldn't be a problem now as the oil cooler is full of oil so will be able to hand prime the oil system before turning over the engine. Will also not be using assembly lube this time just straight run in oil. Also going to open up the oil ways in the crank to improve the flow, just as soon as I find the article on Seloc I was reading about it all on.

edit: must read replies before posting, Robin that's what I was thinking initially but as it is brand new (although that's no guarantee) and it was balanced and checked for run off I didn't think it could be that. On checking some sites with bearing damage the outside wear indicates insufficient oil pressure or "wiping" . Here is the site I was looking at. The other thing is all of the ladder bearings with the exception of number 5 are spot on, no signs of wear what so ever, if the crank was bent some of them should have had high wear spots on them.

[David]

Your photo suggest to me that the bearings did not get any oil, and If you got oil pressure, then it suggest oil starvation to the crank. I'd look closely at alignment of oil galleries between the main bearing/shells/crank. Looks like there could be a miss-match to me.

Good luck

David

[Mikie711]

Cheers David, I think they got oil just not quickly enough. If they had not got any at all then they would have been in far worse shape. I think the problem stems from not priming the oil system effectively prior to turning it over on the starter and then starting the engine. It may well be the damage was done before the engine was even fitted. If you look back to earlier posts after building the engine I noticed a tight spot that seemed to go away once I got oil to the bearings. So likely the bearing was all ready damaged and it was only a matter of time after that.

The same mistake shall not be repeated. I am going to open up and match the oilways between the block and ladder this time as well.

[Mikie711]

Have spoken with Dave Andrews and after checking a couple of things the problem is indeed with the rods. The big ends when bolted up are slightly out of round which is pinching the bearing and given the wrong bearing crush. A nice new set of Fardon rods should sort that out. He also doesn't recommend running VP-2 bearings as they are to hard Trophy 160 bearings are, apparently the way ahead for both mains and big ends. Guess it's a case of 10 different people 10 different opinions but given the extent of his knowledge I take what he recommends.

[robin]

Guess it's a case of 10 different people 10 different opinions but given the extent of his knowledge I take what he recommends.

Yes, I would say that in this case his opinion counts for a lot

Cheers,
Robin

[campbell]

"Trophy 160" bearings...so some aspects of the bottom end of the K were reworked for that MGF variant then, not just the head and intake etc?

Interesting.

[mac]

Aren't the bearing made from a bronze mix anymore?

I would have plumbed with lack of oil too but my engine building experience has only ever been with older cast iron units - although some had have overhead cams.



Mac

[Rich H]

I thought all bearings were white metal on a copper carrier.

[Mikie711]

Apparently not any more, copied from an article about Vandervall new HVOF spraying technique

"Traditionally there are two types of plain bearing, a trimetal and bimetal, both consist of a lining of about 0.25mm of bearing alloy on a steel half shell backing. The bimetal generally has a lining of aluminium-tin alloy to give an aluminium-based matrix with a tin soft phase and is used principally for high volume gasoline passenger cars and some light truck applications. The trimetal has lead-bronze alloy as the lining, to give a copper-tin matrix with a soft lead phase, over which there is a thin, 0.015mm overlay of typically lead-based alloy to give improved resistance to seizure and is used for diesel passenger cars, heavy trucks and high speed gasoline engines where greater strength is need in the bearing alloy. For aluminium bimetals, the manufacturing route is casting of the lining alloy and roll bonding this to the steel substrate. Post-rolling annealing treatments are used to improve bonding and to recrystallise the bearing alloy for improved ductility. For trimetals, the bronze is cast directly onto a steel backing and following bearing manufacture, with the overlay deposited by electroplating or sputtering."

Full page here

[Rich H]

Thanks for that. I'll read it when I'm bored (At work)

[ABZ-Elise]

Note to self...never buy cheap sh!te rods!!

Kev.

[Mikie711]

Ye Kev, definitely a case of "if a deals to good to be true". New ones ordered and this time I'm just going to slap it all together. Turns out that checking the bearing clearances on K series mains using plastigauge is a waste of time as you never get a true reading. So plan is, clean the sh!t out of everything, loads of oil on assembly, bolt it all up and prime the oil system. Throw it back in and fire it up.
Still got a bunch to do to the rest of the car, not least reset all the geometry. Away tomorrow for a month so probably just let this thread die a death now...........................................

[campbell]

Why not start "Winter Strip Down and Rebuild...the sequel" and x-ref the two threads

Be inspirational, sir, you are doing a great job so far

[BiggestNizzy]

Be inspirational, sir, you are doing a great job so far

You make me want to buy another engine

[Mikie711]

Just waiting for my taxi, but managed to get the rack riser plates fitted and the dash put back together. Also finished modifying the oil ways between the block and bearing ladder. Have organized someone to take the new rods down to Agra to have them balanced so everything will be ready when I get home.

And I will see it through to the end with the thread.


Stay safe, see you all in a month.

Mike